Large-area acoustic radiation system

Abstract

The invention relates to acoustically radiating randomly large rooms and surfaces according to propagation time principles, whereby action or representation and reception or listening areas border directly on one another or are identical. Its object is to avoid error locations and skipping effects caused by movements, which are especially interfering for important solo sound sources. The resulting object of realizing a propagation time staggering without limiting source areas, and responding to the acoustic capacity of the sources, is solved by means of a control device connected to the delay or amplification devices, and which differentiatedly controls them analogous to the sound paths between the source and the acoustic radiator locations.

We claim: 
     
       1. In a large-area sound reinforcement system for multi-dimensional extended action and reception areas having several distributed sound radiators and microphones as well as devices for the delay, amplification and non-reactive summation in the microphone sound radiator connections, at least one of the microphones being assigned to a solo source; the improvement wherein at least two of the devices for the delay and for amplification disposed in connections assigned to said one microphone comprise a device for the control of delay times and at least another for the control of amplitudes, wherein, in addition to sound radiators positioned in the transitional area between the action area and the reception area, additional sound radiators distributed in the action area are connected to the output devices for the summation and distribution of said connections, and wherein a control device for said two devices for delay and amplification is comprised of input means for receiving microphone position and sound source power data and for receiving sound radiator position and power data, and a comparison and control device for deriving delay time and amplitude signals for the control of said two of said devices for delay and amplification from the comparison of said position and sound power data. 
     
     
       2. The large-area sound system of claim 1 wherein the input means for the sound radiator powers, for the coordinates of fixedly installed sound radiators and for the sound source powers comprise constant storage devices, and adjustable input panels are used for the coordinates of location-variable solo sources and location-variable sound radiators. 
     
     
       3. The large-area sound system of claim 1 wherein the input means for the sound radiator powers, for the coordinates of fixedly installed sound radiators and for the sound source powers comprise constant storage devices, and adjustable locating devices are used for the coordinates of location-variable solo sources and location-variable sound radiators. 
     
     
       4. The large-area sound system of claim 1 wherein the input means have numerical or digital output values of the sound powers or coordinates, and the comparison and control devices comprise a computer for providing control values for the control of said devices for delay and amplification. 
     
     
       5. The large-area sound system of claim 1 wherein the output devices for the summation and distribution are coupled to a plurality of microphones assigned to a source areea and the signal portions are included in the comparison of sound power. 
     
     
       6. The large-area sound system of claim 1 wherein the control of more than one device for the amplification or summation with regard to the amplitudes comprises multiplying control circuits, the inputs of which are connected to outputs of the control device and of the operating devices for level alignment, and the outputs of which are connected to the control inputs of at least two controllable amplifiers having signal inputs connected to a source. 
     
     
       7. The large-area sound system of claim 1 wherein controllable attenuators are inserted between the output devices for summation and distribution and additional sound radiators in the action area, the control inputs of the attenuators being connected to the output of the comparison and control device extended by a location coincidence test device. 
     
     
       8. The large-area sound system of claim 1 wherein the input means for the microphone locations and sound source powers and comparison and control units have an additional connection to units for the generation of reflections, whereby an adaptation of the degree of simulation of the acoustic sound field to the sound source location and the sound source power can be made. 
     
     
       9. The large-area sound system of claim 2 wherein the adjustable input panels are simulations of action areas having an operating field which represents therein the sound source and sound radiator locations, and the associated comparison device is a combination of these input panels for the proportional shifting of delay time and amplitude steps. 
     
     
       10. The large-area sound system of claim 2 wherein the adjustable inputs panels each consist of one row of switches assignaed to coordinates, on the one hand connected to a common potential and aon the other hand to the inputs of an OR circuit and the up-down control inputs of an up-down counter, the clock inputs of the counter being connected to the output of an AND circuit, the inputs of the AND circuit being connected to the output of the OR circuit and a keying signal of variable frequency, and the data output of the up-down counter being connected by way of a coder to the comparison and control device. 
     
     
       11. The large-area sound system of claim 3 wherein sound measuring signal generators or sound measuring signal receivers are provided for the locating devices and are assigned on the one hand to the location-variable solo locations and at least to two locations at the edges of the actions area on the other hand are coupled with each other and by way of coders to the comnparison and control devices. 
     
     
       12. The large-area sound system of claim 10 wherein sound measuring signal generators are connected to pulsed ultrasound signals generators, microphones are connected to ultrasound receivers, wherein at the end of the electrical or optical transmission path of the microphone, separationn devices are provided, and the clock sigtnals for the ultrasound signal generators and the transmitted recovered Pulses are applied to time comparison circuits to emit pulses of approximately propagation path proportional duration of which the outputs are coupled to the control inputs of the controllable delay or amplification devices, when the test signal generator and sound radiator are disposed at the same location.